There was a talk at RustConf by Raph Levien about his editor, Xi. It almost entirely uses JSON-RPC to communicate through a distributed architecture, and next-level speed is one of his design goals: https://confreaks.tv/videos/rustconf2016-a-modern-editor-bui...
> I've been keeping an eye on Rust's MSVC progress before I consider using it for a real-world project
The latest builds of MSVC claim to have native Rust syntax highlighting and autocomplete, I have not yet tried it myself: https://www.visualstudio.com/news/releasenotes/vs15-relnotes